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From: boyd@prl.dec.com (Boyd Roberts)
Newsgroups: comp.unix.questions,comp.unix.programmer
Subject: Re: How do I tell if STDIN is a PIPE?
Message-ID: <1991Jun4.100025.29803@prl.dec.com>
Date: 4 Jun 91 10:00:25 GMT
References: <653@eskimo.celestial.com> <1991Jun3.141144.23620@leland.Stanford.EDU> <1991Jun3.150851.21915@prl.dec.com> <1991Jun3.175117.9882@leland.Stanford.EDU>
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In article <1991Jun3.175117.9882@leland.Stanford.EDU>, dkeisen@leland.Stanford.EDU (Dave Eisen) writes:
> 
> Of course, it is (my brain slipped when I was typing and I wrote S_IFREG in
> place of S_IFMT). That still doesn't change the point of my posting ---
> on this machine (running ULTRIX 4.1), sb.stmode & S_IFMT is 0 for a pipe.
> 

Yep, that really sucks.  stat(2) on a pipe(2) returns with st_mode == 0.

But, stat(2) on a named pipe returns with st_mode == S_IFIFO | <mode>.
I just checked this out on my 3max (ULTRIX prl313 4.2 0 RISC).

Neat kernel work, guys...  real neat.


Boyd Roberts			boyd@prl.dec.com

``When the going gets wierd, the weird turn pro...''